Remarkable advances in wireless communication technology have enabled communications among people who are far away from each other. In recent, the needs of local area voice communication using a wireless system based on low-cost and simple hardware are rapidly rising. However, since these applications require that the multi-users communicate on the same wireless channel in a small area, the existing voice technologies are not suitable for directly applying to these applications. Therefore, in this paper I propose a novel idea enabling multi-user voice communication. In particular, as a short range wireless solution, I employ the IEEE 802.15.4 based on low power and low cost. However, since originally the standard is not developed for voice communication, we extend the original scheme to be suitable for the voice communication by utilizing the extended concept of GTS. The capacity and validity of the proposed scheme are evaluated through quantitative analysis in various voice compression rates.

Educational robot was introduced as an effective educational tool is to foster scientific creativity and learn the basic principles of science are applied to change the configuration of the educational after-school learning kits for science education. SMEs as a tool to foster scientific creativity center and a variety of educational robot technology and the wide range of games for students and robotic technology development, existing e-Learning by downloading mp3 music or learning content for the robot, such as the provision of specialized content Although the technology is still being developed to take advantage of the professional community formation is insufficient side. Currently, one-point linkage drag Smart Touch control dynamic motor development does not need this motor development is possible for users to easily.

In this paper, we propose a passive microwave sensor for detecting human body using microwave radiometer technologies. The proposed sensor detects human body by measuring the change of the received radiation power from fixed background object due to human body. A C-band microwave radiometer is designed and implemented. The received radiation power changes due to human body is measured by the C-band microwave radiometer, and the effectiveness of the proposed sensor is evaluated by the measurement result analysis.

This study aims to design a chief VDR(Voyage Data Recorder) system which is appropriate to small and medium sized vessels and also implement the data about marine communication devices, sensors, etc. to be stored or printed at the navigator when those data are connected to VDR through data communication between marine navigation and VDR which are based on serial communication or internet in order to prove efficiency of the marine navigator. Also, the design of VDR is intended to be small and light in order to expand to apply it to small and medium vessels, which enables to analyze causes of marine accidents precisely through its characteristic functions which are the same as those at "vehicle mounted black-box" (location of the car, image and voice storage) by which the same roles are played on land.

This research presents a DC-DC converter controller implemented with an analog memory. The structure of the converter will contribute to solve the stability problem unavoidable in a conventional closed loop converter. The analog memory will be used for realizing CAM(Contents Addressable Memory) which contains the output of the converter and the relevant duty ratio, respectively. The operation for reading in the memory is executed with an absolute differencing circuit and a WTA(Winner-Take-All) circuit suitable for a nearest-match function of the CAM. We also present a system architecture that enables highly-paralleled fast writing and quick readout as well as high integration density.

The performance of 4-switch 3-phase inverter(FSTPI) is mainly affected by the unbalanced voltages between two capacitors which replace two switches of conventional 6-switch 3-phase inverter(SSTPI). This paper proposes a DC offset current injection method to compensate the capacitor voltage unbalance for FSTPI. A simplified SVPWM method which can be applied to FSTPI is also proposed. The validity of the proposed methods is verified by computer simulation.

This paper is studied the Korean language to optimize the Hangul character coding for information processing in information terminal device and transmission in network. The paper analyzed Hangul character in Korean language and use frequency of each character. The paper also compared the analysis result to Hangul characters which are coded in standard in Korean character and Unicode. This study referred "Modern Korean Use Frequency Rate Survey Result" issued by The National Institute of the Korean Language. There are total 58,437 Korean words in the report. As a result of this paper, the Korean word 58,437ea are consisted of Hangul character total 1,540ea. The highest use frequency character is "다" and its use frequency to total use frequency rate is 15%. The lowest use character is "휫"and its use frequency to total use frequency rate is 0.00003%. The number of analyzed Hangul character 1,540 is less 7.2 times and 1.5 times than Korean and Unicode standard respectively.

In recent, many researches have been studying sensitivity and psychology of human being on color and the necessity of psychology therapy by color. Among them, a picture of children can be a tool to represent their emotion. Information of colors and direction on a child`s picture often represent his internal psychological states unconsciously and is different from the brightness of a color. In this paper, we propose a method to extract domain colors by color classification and subdivision the classes of brightness using fuzzy inference. In addition, it is shown that our method is used for analysing the psychology status of children through their pictures.

In Electronic Commerce and Secret Communication based on ECC over finite field, if the sender and the receiver use different basis of finite fields, then the time of communication should always be delayed. In this paper, we analyze the number of bases-transformations needed for Electronic Signature in Electronic Commerce and Secret Communication based on ECC over finite field between H/W and S/W implementation systems and introduce the anomalous basis of finite fields using AOP which is efficient for H/W, S/W implementation systems without bases-transformations for Electronic Commerce and Secret Communication. And then we propose a new multiplier based on the anomalous basis of finite fields using AOP which reduces the running time by 25% than that of the multiplier based on finite fields using trinomial with polynomial bases.

In this paper, we propose an efficient gait trajectory generation method for the static stair climbing of a quadruped robot with mechanism of insectile legs, which has no collision with staris. First, we derive the kinematic and inverse models of a quadruped robot using the algebraic and geometrical methods, respectively. In the proposed method, we generate the stair locomotion trajectory of a sine wave after lifting a leg from the start position, and then determine the coefficient of the generated trajectory to avoid the collision with stairs. In addition, we make the gait sequence for the stable stair locomotion. Finally, we verify the effectiveness and applicability of the proposed stair locomotion method through computer simulations.

In this paper, we propose a design method for the position and speed controller, current control of a Brushless Direct Current(BLDC) motor using back-stepping design techniques. Further, to stabilize the whole system, and proposes a method for setting the appropriate gain control to improve the tracking performance. By applying the proposed controller to 120W BLDC motors were tested for the ability to follow the position, velocity and current reference. Since the simulation results of the steady state error is within 1%, we were able to show the usefulness of the tracking performance of the proposed controller.

As the elderly are increasing, traffic accidents which are related to the elderly are one of major issues in aged society. In this paper, we analyze traffic accident statistics for the elderly. Based on the analyzed data, safety message transmission system for the elderly pedestrians is introduced. The proposed system is based on the P2V(Pedestrian-to-Vehicle) communication which combines ICT(Information and Communication Technology) with vehicles and pedestrians. We introduce the concept and principle of the proposed system and discuss implementation issues for realizing the proposed system.

The era of IoT in which all objects are intelligent and are connected to the Internet has been started. In order to establish and activate an IoT eco system, open services platform is very important. In this paper, we developed a BLE sensor module as a component of the open service platform based on the IoT and the open source hardware Blutooth4.0. To verify the functionality and performance of the developed BLE sensor module was built to evaluate the performance of the test environment.

The objective of this study was to effect of Tai Chi on balance and muscle activity of ankle joints with USN sensor in elderly people. Thirty six elderly participated and randomly assigned to a experimental group with Tai Chi and control group. The experimental group trained using a Tai Chi through 3 times per a week over 6 weeks. For all subjects, their balance such as functional reach test and one leg stance test, the change of muscle activity of ankle joints with USN sensor wireless-electromyogram during leg closed stance with eye closed were measured, and the results were as followed. The results were of a signigicant changes to the balance in group and between group as well. Comparison of muscle activity left tibialis anterior and left gastrocnemius in group, there were significant difference. Comparison of muscle activity right tibialis anterior and right gastrocnemius in group, there were significant difference. Comparison of muscle activity between groups, there was significant difference. Additional results indicated that, elderly people who received Tai Chi in one study, improve balance control and muscle activity ankle joint. so it is anticipated that improvement in clinical utilization for the elderly who`s gait ability and balance ability reduced.